Examples of known electrowetting display devices include single layer displays comprising one oil layer and two layer displays including two oil layers separated from each other by water. In these examples, the oil layers may be coloured and switched independently to change a display effect of the device, for example a colour or a grey scale.
Electrowetting devices including single oil layer displays and multi layer displays, for example with opposing portions of liquid which may be advanced or retreated over an aperture to change a display effect, are also known.
A disadvantage of such systems is that to change the configuration of the oil layer(s), a high operating power is required. Moreover, such systems require complex electronics for addressing both oil layers.
It is desirable to provide an improved electrowetting display device.